Pulling parasites from the blood with a souped-up kid’s toy

ie together some twine, a sheet of paper, and a little bit of plastic and pull — you’ve got a toy whirligig. Or human-powered blood centrifuge.

Scientists have created the new “paperfuge” — which costs about 20 cents to make — to separate blood plasma from red cells in just a minute and a half. They’re currently working on clinical validation studies; so far, it’s just a proof of concept prototype.

What inspired the idea behind the paperfuge?

Every single lab or diagnostic facility uses a centrifuge. Our constraint was to make something that was purely human-powered but that could meet the standard used in diagnostics. We wanted to make it extremely low-cost and affordable. And for it to work in areas where there’s no electricity, in developing countries, we wanted them to be human-powered. As a team we looked thorough many many toys. We started with yo-yos, we moved to tops, and eventually we stumbled upon a toy called a whirligig.

What went into making it?

We realized that nobody actually understood the mathematics and the physics behind the toy, which can’t move fast enough. But when you understand the parameters, you can adjust them and achieve all the way up to 125,000 revolutions per minute. So you can actually pull out malaria parasites, African sleeping sickness, and all kinds of other different parasites from blood.